1. Field of the Invention
The present invention relates a system that responds to incoming telephone calls by dynamically generating a source file of caller-specific audio content, and then utilizing the source file to conduct an interactive playback session audibly presenting the audio content to the caller. The invention supplements source files with internally stored history records for purposes such as increasing the functionality of interactive user playback, providing billing records, aiding debugging, and preserving data that is useful for marketing purposes.
2. Description of the Related Art
VoiceXML is a markup language for representing human-computer dialogs, analogous to the hypertext markup language (HTML). Unlike HTML, which utilizes a graphical web browser, with display, keyboard, and mouse, VoiceXML utilizes a voice browser with audio output (computer-synthesized and/or recorded), and audio input (voice and/or keypad tones). The typical VoiceXML voice browser runs on a specialized voice gateway node that is connected both to the public switched telephone network (PSTN) and to the Internet. These voice gateways extend the power of the worldwide web to telephones of all sorts, from traditional land line phones to wireless or even satellite phones.
VoiceXML is particularly suited to a number of different technologies. One example pertains to information retrieval applications. Here, output tends to be pre-recorded information, and voice input often consists of a few navigation commands and limited data entry (e.g., a few commands to browse a set of news articles, or the collection of zip code for a weather forecast). One approach is a system in which users enroll for a voice newsletter at a web site and specify their interests, and then call in periodically to listen to their newsletter and browse through its articles. Information retrieval applications can provide general or more specialized information (e.g., intranet-based company news), and may be funded by subscription, advertisement, connect time, etc.
Another area suitable for VoiceXML is electronic commerce. Catalog ordering applications may be implemented if the customer has a printed catalog, or knows the exact product already, or if the products can be described briefly and there is a small number of them. Customer service applications such as package tracking, account status, and call centers are well suited to VoiceXML. Financial applications such as banking, stock quotes and trading are also well suited to VoiceXML.
Some other areas that are ripe for VoiceXML include (1) telephone services such as personal voice dialing, one-number xe2x80x9cfind-mexe2x80x9d services, teleconference room setup and management, (2) intranet applications such as inventory control, ordering supplies, providing human resource services, and corporate portals, and (3) unified messaging applications such as e-mail, voice-oriented address information, origination or routing of pager messages, and (4) many others. Further information about VoiceXML is available from the VoiceXML Forum, a program of the IEEE Industry Standards and Technology Organization (IEEE-ISTO), and may be found at the internet address http://www.voicexml.org.
Although VoiceXML and its known applications provide numerous benefits today, INDICAST CORPORATION (xe2x80x9cINDICASTxe2x80x9d) has sought improvements in the performance and efficiency of traditional audio content rendering. Relatedly, INDICAST is the assignee of co-pending U.S. patent application Ser. No. 09/653,472, filed on Aug. 31, 2000 in the names of T. Todd Elvins et al. and entitled xe2x80x9cSYSTEM AND METHOD FOR GATHERING, PERSONALIZED RENDERING, AND SECURE TELEPHONIC TRANSMISSION OF AUDIO DATA.xe2x80x9d The entirety of the foregoing application is hereby incorporated herein by reference. Nonetheless, the present inventors have encountered a number of limitations of VoiceXML when applied to more intensive tasks involving the rendering of audio content to telephone callers. Still, extending the VoiceXML language would require a large software development effort and any deviation from the VoiceXML standard would make such a solution non-portable.
Consequently, the state of the art is not completely adequate due to certain unsolved problems.
Responsive to an incoming telephone call, a session server first consults pre-stored caller preferences to generate a source file of caller-specific audio content, and then proceeds to conduct an interactive playback session audibly presenting the audio content to the caller. An exemplary source file is a VoiceXML file containing and/or referencing the audio content. Each call""s source file includes an internally stored history record documenting events that occur during playback, such as caller utterances, identity of audio content presented, voice prompts presented to the caller, errors, and time stamps of various playback events. In response to certain caller utterances or completion of the source file""s presentation, the session server may reference the history record to create an appropriate follow-up source file containing supplementary audio content. The history records may be used to increase the functionality of interactive user playback, generate billing records based on content play time, aid in debugging efforts, preserve data indicative of customer tastes for marketing purposes, and other uses.
The foregoing features may be implemented in a number of different forms. For example, the invention may be implemented to provide a method of enhanced interactive playback of audio content to telephone callers according to pre-selected caller preferences, as described herein. In another embodiment, the invention may be implemented to provide an apparatus such as an audio information delivery system, as discussed herein. In still another embodiment, the invention may be implemented to provide a signal-bearing medium tangibly embodying a program of machine-readable instructions executable by a digital data processing apparatus to perform enhanced interactive playback as described herein. Another embodiment concerns logic circuitry having multiple interconnected electrically conductive elements configured to perform enhanced interactive playback as described herein.
The invention affords its users with a number of distinct advantages. Unlike VoiceXML and other known languages, the present invention creates a log representing playback, input, and error events. This log, the history record, is useful in many different ways. For example, by using a history record to maintain state across phone calls, the audio information delivery system of the invention carefully tailors playback services to each particular caller""s interactive playback use-history. For instance, history records enable the audio delivery system to resume dropped calls from the point where playback ended, without the need for unnecessary, time-consuming interaction with the caller to regain perspective. Along these lines, when a new call is received, the audio information delivery system may use history records to skip over content played for the caller during previous playback sessions. As another advantage, the invention uses its history record feature to record play time, which is subsequently helpful for billing purposes, such as tracking play time for payment of content providers, or tracking play time for billing callers for their use of playback services. History records may also be used for data mining, recreating calls to debug software, conducting user studies, and the like. Moreover, the invention provides a voice-user interface that is user-friendly in several respects. For instance, the invention""s use of history records accommodates playback re-ordering responsive to users"" commands such as back-up, previous channel, next channel, etc. The invention also provides a number of other advantages and benefits, which should be apparent from the following description of the invention.